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Messages - dmtaylor

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31
All Grain Brewing / Re: Batch sparge volume and temp trouble
« on: April 03, 2018, 11:32:31 AM »
15 pounds of grain at 1.5 water to grain ratio + deadspace + grain absorption from the software gives me 26 quarts of strike water.

Sparge volume is correct.  It's the strike volume that's too high.  You should account for grain absorption but NOT deadspace in the strike calculation.  If you want a ratio of 1.5 qt/lb, I'd strike with just 22.5 qts for your 15 lb grain.  If you strike with 26 qts, you're a gallon high.

FYI -- my batch sparge water is usually about 190 F.  It doesn't hurt anything to go above 170 F because once it's all blended together, it will only hit about 160-165 F anyway.  Probably could/should use boiling water actually if a mashout is desired.

32
Kegging and Bottling / Re: Bottling a Dark Strong
« on: April 02, 2018, 11:54:58 PM »
Plenty of yeast.  No worries.

33
All Grain Brewing / Re: pH?
« on: April 01, 2018, 11:39:42 AM »
My honest informed opinion:  If your beer tastes good, then don't go down the rabbit hole cuz it truly ain't worth it.  Seriously.

34
Kegging and Bottling / Re: Commercial bottles
« on: March 31, 2018, 03:56:00 PM »
I was thinking about using 12 oz commercial beer bottles with standard caps for bottling my beer, are they safe to use?

After using commercial beer bottles more than 4000 times, I can definitely say: YES, they're fine.

35
Here's a couple more:

Carapils is worthless.  It doesn't do what anyone says it does.

There is no magic about corn sugar for priming either.  Use table sugar.  You already have some in your kitchen cupboard, it's cheap and it's effective.  (Keggers need not respond to this either, thanks.)

36
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 29, 2018, 12:55:50 PM »
I've always read (someone confirm or correct this?) that we humans just can't distinguish a difference of +/- 5 IBU.  Therefore,  the upshot of this should be, keep your hops in the freezer, and for years you can just act like the alpha on the label is real. Tell Beersmith to RDWHAHB.

I've heard the detectability notches are anywhere from 2-5 IBUs apart.  Personally I believe the notches spread every 3 IBUs... but I haven't done lab analysis or blind tastings to prove this either.  Numbers like 2-3 IBUs have been thrown around in more recent years.  4-5 IBUs are the "older" numbers, if that means anything (heh... thinking back on homebrewers in 1993!).

But you're right.  A loss of a fraction of a percent of alpha over a year or two is not going to make a huge difference, assuming we store the hops cold and well sealed.  Conversely, if not stored well, then all bets are off.

37
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 29, 2018, 10:44:45 AM »
Dave, two things:

(1) I don't think you _can_ really ignore beta.  It oxidizes to soluble form at essentially the same rate that alpha is lost, so it offsets alpha loss to a significant degree.  (This explains how landrace varieties were selected: they exhibit near 1:1 alpha:beta and so had _apparently_ better storage stability.)

(2) Why are we still awake and on this forum, man?

Yup and yup, I agree and I agree.

The IBU totally ignores alpha, so why shouldn't we.

I was up till 11pm and now here I am up for work at 5:44am.  Icky.  But at least I don't have to work tomorrow.  :)

38
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 29, 2018, 04:12:31 AM »
Okay......... I've spent a couple more hours pondering the ancient Garetz article.

My thoughts:

The Garetz-Nickerson formulae are indeed based on Arrhenius as I mentioned previously, but they claim that degradation reaction rate doubles for every 15 C, not every 10 C as many other reactions do and that I mentioned before.  Okay.  I can accept that.

The data and equations were finalized in about 1993.  I believe hop harvest and storage technology has come a little ways since 1993.  As such, I propose that the Storage Factor SF from Table IV might be as low as 0.25, or for fun let's say it is 0.33, i.e., a little bit better than the 0.5 minimum possible back in 1993.

Digging a little deeper and pulling up some old Nickerson references, it appears both alpha and beta acid losses are accounted for here, not just alpha.  So, part of the loss I think is beta.  But for conservatism, we can ignore beta and assume it's all alpha that is lost.  Alright.

Now for average hops' sake, I won't assume every hop is as bad as Cascade for storability per Table I (Cascade was said to be determined to lose 50% alpha and beta at 68 F over 180 days).  Let's go with an average joe hop that loses an assumed 33% alpha (ignoring beta) after 180 days.  This is what Garetz calls "%Lost".

From %Lost, go to Table II (which I verified accurate), and you get a rate constant k of 0.00222 for 33% lost for average-joe hop.

Now, storage temperature..... I know I have my freezer set at exactly 5 F.  Others might have their hops stored in the refrigerator at say 35 F.  Let's see how that computes..... For 5 F, Table III (also verified accurate) says the Temperature Factor TF is 0.198.  And at 35 F, TF would be about 0.430.  Hmm.  Let's see what effect that has....

Pumping all the numbers into the bastardized Arrhenius equation, let's say for average-joe hop of initial 6.4% alpha, stored at 5 F or 35 F for 180 days, the maths look like this:

future alpha = 6.4/exp(0.00222*0.198*0.33*180) = 6.24% alpha (5 F) or
future alpha = 6.4/exp(0.00222*0.430*0.33*180) = 6.05% alpha (35 F)

So, whether stored in the fridge or in the freezer, I figure we've lost at most 0.35% alpha for average-joe hop after 6 months.

This all assumes a vacuum or nitrogen sealed pack, which I think most of us are doing these days.  If not, it would be beneficial.

The same hop back in 1993 might see a loss more towards... 6.4/exp(0.00222*0.430*0.5*180) = 5.87% alpha

which I'm saying would be due to hop growers back in the old days not doing as good a job of packaging hops early after harvest, and the less stellar packaging materials and methods compared to today.

What does all this mean?

To me it means that the freezer is still better than the fridge, but in either case, let's keep that oxygen out of there if we can, m-kay?  I haven't run a lot more numbers but you can see that if you are storing your hops as well as humanly possible, you're really NOT going to lose much alpha at all over time, and they'll keep for YEARS in either the fridge (pretty good) or freezer (awesome).

And there now you have the results of my geekiness to ponder for your enjoyment.  :)

EDIT: And I still don't know exactly what makes different hop varieties SO very different on Table I.  I don't really believe the variance can be so much, from 15% loss with one hop to 50% for another.  I'll bet those percentages are good to about a half a sig fig --  they seem pretty rough -- but I don't have the source data to know that for a fact either.

39
Beer Recipes / Re: mexican'ish' lager
« on: March 28, 2018, 09:15:44 PM »
Pureed limes will add pithy bitterness.  Maybe shoot for just 10 IBUs.  Yes I'm serious.

Looks good otherwise.  I would drink LOTS of it.

What yeast??

40
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 28, 2018, 08:19:09 PM »
Since I store my hops in the freezer, I also ignore alpha loss calculations. Those alpha loss calculations do seem to be too conservative based on my experience.
Don't the figures for alpha loss assume storage at 0°C?  It would seem a home freezer at 0°F (-18°C) offers a real advantage!
No, the reference is 20C, 68F.

I haven't checked all the references so carefully, but if true and the calculators are based on 20 C, but most brewers are storing the hops at 0 C, then per Arrhenius general rule of thumb where chemical reaction rates double for each 10 C rise, we should expect degradation to occur at approximately 25% (0.5 squared) at 0 C compared with whatever the calc spits out.  This seems to correspond with our experiences pretty well -- I said 1/2 but maybe it really is 1/4 as much loss as "they" say.  I'm pretty busy at the moment (so why the hell am I writing this??) but if I remember I will check more references tonight or this weekend....

41
I think I got the following recipe from BYO magazine in 2008.  I haven't brewed it but I tasted a friend's clone and scored it 43 per BJCP guidelines at the time.

One thing I do know is that they definitely use whole hop cones, not pellets.  Don't know about boil time.

Also mentioned for the recipe below is that they did NOT dry hop, at least not in 2008.

Sierra Nevada Pale Ale Clone
6.5 gallons

OG=1.053
FG=1.011
ABV=5.6%
IBU=32
SRM=7

11.5 lb Pale Malt (2-Row)
1 lb Crystal 60
0.5 oz Magnum (13.6% alpha, 60 min)
0.5 oz Perle (7.7% alpha, 30 min)
1 oz Cascade (5.8% alpha, 10 min)
2 oz Cascade (5.8% alpha, flameout)
US-05

Mash at 153 F for 1 hour.  Ferment 7 days at 68 F.  Dry hop IF desired, but Sierra Nevada doesn't.  Carbonate as normal.

42
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 28, 2018, 10:53:33 AM »
In my experience, I don't find hops to lose as much alpha acid over time as some sources suggest.  Maybe 10% per year.  Maybe it's dependent on the particular strain, but if so, I don't understand why because it's all the same chemical family.

I don't understand the mechanism either, but I do know it varies widely by hop variety.  Here is an excellent write-up on the topic.  Scroll down 2/3 of the way and it will list common varieties with typical losses: https://www.morebeer.com/articles/storing_hops_properly

Yeah... I have my doubts as to the accuracy.  If we assume that our well stored hops lose 0.1% alpha every 37 days, your IBUs will be WAY off after say 296 days after they'd supposedly lost 0.8%.  That's way off.  I have used old hops that were 2-3 years old MANY times and they only ever lose maybe 0.5% or something like that based on real taste.  If you go by the calc, your beer WILL be too bitter.  The calcs are conservative.  Just like mrmalty.com.  Figure these calculators double all their results, cut them in half, and you'll be alright.

43
General Homebrew Discussion / Re: Split up brew Day...?
« on: March 28, 2018, 10:46:29 AM »
Using your uncorrected numbers you are actually around 1.010-1.012 neighborhood.

Yup.  On my refractometer with correction factor of 0.99, it would be 1.012, with 73% attenuation and 4.4% ABV.  Not too bad.

44
General Homebrew Discussion / Re: Adjusting hop alpha acids
« on: March 28, 2018, 12:36:54 AM »
In my experience, I don't find hops to lose as much alpha acid over time as some sources suggest.  Maybe 10% per year.  Maybe it's dependent on the particular strain, but if so, I don't understand why because it's all the same chemical family.

45
General Homebrew Discussion / Re: Split up brew Day...?
« on: March 27, 2018, 09:48:02 PM »
I added the cubes in the first couple minutes, but it was mid-160's.  I do have a pack of US-05 that I can try if needed, but I'm interested in what you said about measuring FG.  I am using a refractometer, but this is new to me.  I was NOT aware that they don't work well for FG and perhaps this could explain why I'm seeing this... these are the first two beers I've used it on.  I did calibrate it right before measuring yesterday.  Is there a calculator you recommend?

Well heck... that ain't a valid reading then!

The calculator I recommend is discussed in GREAT detail here:

https://www.homebrewersassociation.org/forum/index.php?topic=28544.0

And the one that everyone else in the universe recommends, and is easier to use, is here:

http://seanterrill.com/2012/01/06/refractometer-calculator/

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